BACOG uses a standard problem-solving approach to data processing for a 600 square mile study area, a geographic area slightly larger than the average Illinois county. The project estimates the distribution of aquifer materials in the shallow aquifer system and the locations of groundwater recharge areas.

The BACOG method incorporates all available data within the study area and continues to incorporate new data as it becomes available to improve spatial accuracy. The existing database contains approximately 25,000 well logs.

The approach estimates the average hydraulic conductivity, or ability of soil to transmit water, and gives a mathematical estimation of this characteristic at each well location and in areas between well points.

The data and model have error, uncertainty, spatial inaccuracy, and variance that are contained in all models. Because the approach is mathematical and uses a large body of data, it is objective and minimizes error to the extent possible.